RESEARCH ARTICLE
Impact of the Preoperative Controlling Nutritional Status (CONUT) Score on the Survival after Curative Surgery for Colorectal Cancer Yasuhito Iseki, Masatsune Shibutani*, Kiyoshi Maeda, Hisashi Nagahara, Hiroshi Ohtani, Kenji Sugano, Tetsuro Ikeya, Kazuya Muguruma, Hiroaki Tanaka, Takahiro Toyokawa, Katsunobu Sakurai, Kosei Hirakawa Department of Surgical Oncology, Osaka City University Graduate School of Medicine, Osaka, Japan *
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Abstract Background
OPEN ACCESS Citation: Iseki Y, Shibutani M, Maeda K, Nagahara H, Ohtani H, Sugano K, et al. (2015) Impact of the Preoperative Controlling Nutritional Status (CONUT) Score on the Survival after Curative Surgery for Colorectal Cancer. PLoS ONE 10(7): e0132488. doi:10.1371/journal.pone.0132488 Editor: Pei-Yi Chu, School of Medicine, Fu Jen Catholic University, TAIWAN Received: December 18, 2014
Recently, the preoperative immune-nutritional status has been reported to correlate with the survival rate in patients with colorectal cancer (CRC). However, there have been no reports on the relationship between the controlling nutritional status (CONUT) score and the clinical outcome after curative surgery for CRC. We herein evaluated the prognostic significance of the CONUT score in patients with CRC, and then compared the accuracy of the CONUT score and the prognostic nutritional index (PNI) as a predictor of survival.
Methods We retrospectively reviewed a database of 204 patients who underwent curative surgery for Stage II/III CRC. Patients were divided into two groups according to the CONUT score and the PNI.
Accepted: June 15, 2015 Published: July 6, 2015 Copyright: © 2015 Iseki et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Results The five-year cancer-specific survival (CSS) rate was significantly higher at 92.7% in the low CONUT group, compared to a rate of 81.0% in the high CONUT group (p=0.0016). The five-year CSS was 71.2% in the low PNI group and 92.3% in the high PNI group, which showed a significant difference (p=0.0155). A multivariate analysis showed that lymph node metastasis and the CONUT score were independent risk factors for CSS.
Data Availability Statement: All relevant data are within the paper. Funding: The authors have no support or funding to report. Competing Interests: The authors have declared that no competing interests exist.
Conclusion This study suggested that the CONUT score is a strong independent predictor of the survival among CRC patients.
PLOS ONE | DOI:10.1371/journal.pone.0132488 July 6, 2015
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Prognostic Significance of CONUT in CRC Patients
Introduction Colorectal cancer (CRC) is the third most common cancer in the world [1]. Although the surgical procedures and chemotherapy for CRC have improved, the clinical outcome of CRC is still poor, as one-third of the patients who undergo curative resection die within five years after surgery [2]. Therefore, it is necessary to identify biomarkers that can predict the prognosis and individualize the therapy based on the stratification of risks. Many studies about the potential prognostic factors for CRC have been carried out, and the preoperative immune-nutritional status has been reported to correlate with the survival for CRC [3–7]. Recently, the prognostic nutritional index (PNI), which was calculated from the serum albumin concentration and the total peripheral lymphocyte count, has been used to predict the risk of postoperative complications [8], and it has also been reported to correlate with the survival in CRC patients [3, 9]. Regarding the PNI, we consider that the serum albumin concentration tends to be excessively emphasized. However, the serum albumin concentration has been reported to be easily influenced by not only the nutritional status, but also by changes in the body fluid volume, such as those due to the dehydration/fluid retention status and inflammation caused by chronic disease [10, 11]. Therefore, this study focused on evaluating the Controlling Nutritional Status (CONUT) score [10]. The CONUT score is an index calculated from the following factors; the serum albumin concentration, the total peripheral lymphocyte count and total cholesterol concentration. Total cholesterol concentration has also been reported to correlate with the progression of cancer [11]. A more accurate evaluation can be obtain by reducing the importance of the serum albumin concentration and adding the total cholesterol concentration to the evaluation criteria [12]. Although the prognostic significance of the PNI has been reported in numerous previous reports, there have been no reports on the relationship between the CONUT score and the clinical outcome after curative surgery for CRC. The aim of this retrospective study is to determine whether the preoperative CONUT score could be a useful predictor of the survival in patients with CRC, and to compare the accuracy of the CONUT score and the PNI as a predictor of the survival rate of such patients.
Patients and Methods Patients We retrospectively reviewed a database of 204 patients who underwent curative surgery for Stage II/III CRC at the Department of Surgical Oncology, Osaka City University, Japan between April 2004 and December 2009. We performed a retrospective review of 204 patients with Stage II or III CRC. We obtained written informed consent from the patients for participation and the study protocol was approved by the ethics committee of Osaka City University. Our investigation was conducted according to the principles expressed in the Declaration of Helsinki. The resected specimens were assessed using The International Union Against Cancer (UICC) staging classification of colorectal cancer [13]. All patients were followed up until April 2012 or until their deaths. The indications for undergoing adjuvant chemotherapy included patients with Stage III or high-risk Stage II disease. T4 tumors, lymphatic vessel invasion, blood vessel invasion, highgrade histology, presentation with obstruction/perforation and inadequate lymph node sampling were defined as high-risk Stage II disease. The decision of whether or not the patients should undergo adjuvant chemotherapy was determined by the surgeons with the patients’ consent. The doctors judged the indication for chemotherapy, for example, the criteria, performance status, general condition, age and patient’s wishes.
PLOS ONE | DOI:10.1371/journal.pone.0132488 July 6, 2015
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Prognostic Significance of CONUT in CRC Patients
Table 1. Assessment of the nutritional status using the CONUT score. None
Light
Moderate
Severe
Serum albumin (g/dL)
3.50
3.00–3.49
2.50–2.99
